Endomicroscopy is a technique to visualize microscopic structures of internal tissues through tubular instruments that can be inserted through a small cut or an opening in the body. There has been a growing demand for miniaturizing endoscopic instruments while preserving a high resolution to achieve a real-time histopathologic diagnosis. Meanwhile, there has recently been tremendous progress in the coherent manipulation of light in which an optical wave is deterministically manipulated through a linear, disordered medium for optical focusing and imaging. Here, we review recent research efforts in developing new endomicroscopic imaging schemes based on the coherent formulation and manipulation of optical fibers. In contrast to the conventional schemes using optical fibers as incoherent channels for optical power, these approaches provide a route to fully exploiting useful information transmitted through an ultrathin probe, thereby potentially achieving practical endomicroscopic imaging through a submillimeter thick probe.